dedalozzo / eoc-server

src/EoC/Command/MapDocCmd.php

<?php


/**
 * @file MapDocCmd.php
 * @brief This file contains the MapDocCmd class.
 * @details
 * @author Filippo F. Fadda
 */


namespace EoC\Command;


/**
 * @brief Maps a document against every single map function stored into the server.
 * @details When the view function is stored in the server, CouchDB starts sending in all the documents in the
 * database, one at a time. The server calls the previously stored functions one after another with the document
 * and stores its result. When all functions have been called, the result is returned as a JSON string.\n\n
 * The argument provided by CouchDB has the following structure:
 @code
   Array
   (
       [0] => Array
       (
           [_id] => 32012
           [_rev] => 1-f19919e544340438babac6cc86ec61d5
           [title] => Visual Modelling with Rational Rose 2000 and UML
       )
   )
 @endcode
 */
final class MapDocCmd extends AbstractCmd {
  use CmdTrait;


  public static function getName() {
    return "map_doc";
  }


  // @brief Converts the array to an object.
  // @return object
  public static function arrayToObject($array) {
    return is_array($array) ? (object)array_map(__METHOD__, $array) : $array;
  }


  public function execute() {
    $doc = self::arrayToObject(reset($this->args));

    $this->server->getMonolog()->addDebug("MAP ".$doc->_id);

    // We use a closure here, so we can just expose the emit() function to the closure provided by the user. We have
    // another advantage: the $map variable is defined inside execute(), so we don't need to declare it as class member.
    $emit = function($key = NULL, $value = NULL) use (&$map) {

$emit is not used, you could remove the assignment.

      $map[] = array($key, $value);
    };

    $closure = NULL; // This initialization is made just to prevent a lint error during development.

    $result = []; // Every time we map a document against all the registered functions we must reset the result.

    foreach ($this->server->getFuncs() as $fn) {

This code seems to be duplicated across your project.

      $map = []; // Every time we map a document against a function we must reset the map.

Consider using a different name than the imported variable $map, or did you forget to import by reference?

      // Here we call the closure function stored in the view. The $closure variable contains the function implementation
      // provided by the user. You can have multiple views in a design document and for every single view you can have
      // only one map function.
      // The closure must be declared like:
      //
      //     function($doc) use ($emit) { ... };

67% of this comment could be valid code. Did you maybe forget this after debugging?

      //
      // This technique let you use the syntax '$emit($key, $value);' to emit your record. The function doesn't return
      // any value. You don't need to include any files since the closure's code is executed inside this method.
      eval("\$closure = ".$fn);

It is generally not recommended to use eval unless absolutely required.

      if (is_callable($closure)) {
        call_user_func($closure, $doc);
        $result[] = $map;
      }
      else
        throw new \BadFunctionCallException("The map function is not callable.");
    }

    // Sends mappings to CouchDB.
    $this->server->writeln(json_encode($result));
  }

}